Automatic dinnerware making machine



A. C. MUELLER ET AL AUTOMATIC DINNERWARE MAKING MACHINE Sept. 27, 19552,718,683

Filed May 25, 1952 12 Sheets-Sheet l l N V EN TORS.

ADALBERT C.MUELLER CECIL E. ADAMS gfmgm ATTORNEY Sept. 27, 1955 A. c.MUELLER ET AL 2,718,683

AUTOMATIC DINNERWARE MAKING MACHINE Filed May 23, 1952 12 Sheets-Sheet 2IN VEN TORS ADALBERT c. MUELLER FIG By GEGIL EQADAMS ATTORNEY Sept. 27,1955 A. c. MUELLER ET AL AUTOMATIC DINNERWARE MAKING MACHINE l2Sheets-Sheet 3 Filed May 23, 1952 INVENTORS ADAL B ERT C. MUELLER yCECIL E. ADAMS MAG/6557M ATTORNEY Sept. 27, 1955 A. c. MUELLER ET ALAUTOMATIC DINNERWARE MAKING MACHINE 12 Sheets-Sheet 4 Filed May 23, 1952FIG.11.

FIG 10.

INVENTORS ADALBERT G. MUELLER By CECIL E. ADAMS ATTORNEY Sept. 27, 1955A. c. MUELLER ET AL AUTOMATIC DINNERWARE MAKING MACHINE l2 Sheets-Sheet5 Filed May 23, 1952 INVENTORS ADALBERT C. MUELLER BY CECIL E. ADAMSATTORNEY Sept. 27, 1955 A. c. MUELLER ET AL 2,718,683

' AUTOMATIC DINNERWARE MAKING MACHINE Filed May 23, 1952 12 Sheets-Sheet6 222 FIG. l5

INVENTORS 224 RT 0. MUELLER CECIL EADAMS /QQMAMM ATTORNEY Sept. 27, 1955A. c. MUELLER ET AL 2,

AUTOMATIC DINNERWARE MAKING MACHINE Filed May 25, 1952 12 Sheets-Sheet'7 INVENTORS ADALBERT C. MUELLER BY CECIL E.ADAMS ATTORNEY A. c. MUELLERET AL 2,718,683

AUTOMATIC DINNERWARE MAKING MACHINE 12 Sheets-Sheet 8 F I6. I?

INVENTOiG ADALBERT C. MUELLER BY CECIL E. ADAMS ATTORNEY Sept. 27, 1955Filed May 25, 1952 P 1955 A. c. MUELLER ET AL AUTOMATIC DINNERWAREMAKING MACHINE l2 Sheets-Sheet 9 Filed May 23, 1952 Emmmmm Oh INVENTORSADQLBERT C. MUELLER BY CECIL E. ADAMS flwmzm ATTORNEY Sept. 27, 1955 A.c. MUELLER ET AL AUTOMATIC DINNERWARE MAKING MACHINE l2 Sheets-Sheet 11Filed May 25, 1952 FIGHZIO.

INVENTOR.

ADALBERT O. MUELLER By CECIL E. ADAMS mmuam ATTORNEY Sept. 27, 1955 A.c. MUELLER ET AL 2,718,683

AUTOMATIC DINNERWARE MAKING MACHINE Filed May 25, 1952 12 Sheets-Sheet12 FIG. 21.

INVENTORS ADALBERT G. MUELLER BY CECIL E. ADAMS ATTORNEY United StatesPatent AUTOMATIC DINNERWARE MAKING MACHINE Adalbert C Mueller and CecilE. Adams, Columbus, Ohio, assignors to The Denison Engineering Company,Columbus, Ohio Original application December 8, 1945, Serial No.633,782, now Patent No. 2,557,884, dated June 19, 1951. Divided and thisapplication May 23, 1952, Se-

. rialNo.289,545

Claims. (Cl. 25-23) This invention relates generally to the ceramic artand is more particularly directed to mechanism for automatically formingclay or similar plastic materials into dinnerware and like articles.

This application is a divisional application of our copendingapplication Serial No. 633,782, filed December 8, 1945, for AutomaticDinnerware Making Machine, now Patent No. 2,557,884, dated June 19,1951.

An object of this invention resides in providing an automatic dinnerwaremanufacturing machine which may be continuously operated to supply clayto means for severing the same into bats which are positioned on molds,to press the bats into the approximate shape of the article desired andthen to jigger the previously pressed pieces into the final shape afterWhich the molds with the formed pieces thereon are removed from themachine for drying.

Another object of the invention is to provide a machine for makingdinnerware having a table-like carrier above which clay feed and cut-offmeans, forming dies and jiggering devices are supported in spacedrelation, the machine also having means for rotating the carrier step bystep to successively position molds carried thereby in registration withsuch devices and means actuated by fluid pressure at points of stoppageof said molds for moving the latter from the carrier to position whereinclay bats disposed on the molds may be operated upon by the dies andjiggering devices.

It is also an object of the invention to provide a pair of the machinesmentioned in the preceding paragraph, dispose the machines in adjoiningrelationship and synchronously operate them, a conveyor being disposedbetween the machines to simultaneously deliver empty molds thereto andremove loaded ones therefrom, each of the machines being furtherprovided with dual clay feeding means so that both may be continuouslyoperated to secure high production rates, the machines and the clayfeeds being actuated in part by fluid pressure whereby smooth, uniform,relatively quiet operation will be secured.

Another object of the invention is to provide a dinnerware makingmachine of the type mentioned in the preceding paragraphs havingimproved fluid pressure operated means for moving molds with clay batsthereon into and out of their various forming positions, the machinehaving mechanism for controlling the admission of fluid pressure to themold moving means whereby the maximum output of the machines will besecured without any decrease in quality of the ware.

A further object is to provide the hydraulically operated mold movingmeans with control mechanism which will so govern the flow of pressurefluid to such means that the molds will be moved with a uniformlyaccelerated and decelerated motion toward the forming means, jerkinessand possible damage to the bats being formed thus being avoided.

A still further object of the invention is to provide a dinnerwaremaking machine having mold moving means ice including a power cylinderand piston and a control mechanism with valve elements which are movableboth relatively and in unison and providing means for moving theelements, one of such means being directly responsive to the movement ofthe piston of the power cylinder. The mechanism is thus renderedsensitive and positive in operation, simple and easy to maintain andservice.

Another object of the invention is to provide the hydraulic system ofthe machine with control mechanism which will stop the operation thereofin the event the proper operating pressures are not maintained, themachine therefore being prevented from producing incorrectly shapedarticles or from injury in the event the various parts of the machineare not operated in the essential sequence.

It is also an object to provide a control mechanism which willdiscontinue the operation of the machine in the event certain conditionsare not maintained and when such conditions are restored will cause thevarious operating parts of the machine to function in the necessarysequence when the operation is resumed.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein a preferred form of embodiment of the invention isclearly shown.

In the drawings:

Fig. 1 is a top plan view, partly in horizontal section, of a dinnerwareforming machine formed in accordance with the present invention.

Fig. 2 is a vertical transverse sectional view taken on the planeindicated by the line IIII of Fig. 1.

Fig. 3 is a similar View taken through the machine on the planeindicated by the line III-III of Fig. l.

' Fig. 4 is a detail horizontal sectional view taken through the base ofthe machine shown in Fig. 3 on the plane indicated by the line IVIV ofFig. 3.

Fig. 5 is a similar view taken on the plane indicated by the line VV ofFig. 3.

Fig. 6 is a plan view of the machine on a reduced scale showing also inplan the means for feeding clay to one side of the machine.

Fig. 7 is a side elevational view of the clay feeding machine shown inFig. 6.

Fig. 8 is a vertical transverse sectional view taken through the clayfeeding mechanism on the plane indicated by the line VIIIVIII of Fig. 7.

Fig. 9 is a similar View taken through the clay feeding mechanism on theplane indicated by the line IX-IX of Fig. 7.

Fig. 10 is also a similar view taken through the clay feeding mechanismon the plane indicated by the line XX of Fig. 7, this figure showingclamping means employed to secure a clay magazine to the power unit usedto expel clay from the magazine to the dinnerware forming machine.

Fig. 11 is a similar view taken through the forward portion of the clayfeeding mechanism on the plane indicated by the line XIXI of Fig. 7.

Fig. 12 is a detail vertical sectional view taken on the plane indicatedby the line XIIXII of Fig. 10.

Fig. 13 is a diagrammatic view of the hydraulic circuit employed tooperate the clay feeding mechanism shown in Figs. 6 and 7. v

Fig. 14 is a vertical longitudinal sectional view taken through apressure building valve by which the volumetric delivery of the pump inthe hydraulic system shown in Fig. 13 is maintained constant.

Fig. 15 is a detail vertical longitudinal sectional view taken throughjiggering mechanism provided on the machine shown in Fig. 1.

Fig. 16 is a detail horizontal sectional view, partly in elevation,taken through a portion of the machine shown in Fig. 3 on the planeindicated by the line XVIXVI of Fig. 3, this figure showing mechanismfor controlling the flow of fluid to the power unit employed to move amold with a clay bat thereon into engagement with a forming die andshowing in elevation, also, the control mechanism for the power unitemployed to move a previously formed bat into engagement with ajiggering tool, the control mechanisms being shown in the relativepositions occupied in the machine.

Fig. 17 is a vertical longitudinal sectional view taken through thecontrol mechanism and the power unit governed thereby, the plane of thissection being indicated by dotted line XVIIXVII of Fig. 16. While theline is bent at several points, the view is made to appear as though theline were straight for the purpose of clarity.

Fig. 18 is a diagrammatic view of the dual pressure hydraulic systememployed in the operation of the pressing and jiggering mechanism.

Fig. 19 is a diagrammatic view of the electrical circuit employed in theoperation of the complete wareforming machine.

Fig. 20 is also a diagrammatic view of a single pressure hydraulicsystem which might be employed in the operation of the pressing andjiggering mechanism, a standby motor and pump being provided to avoididle periods in the event service is necessary on one or the other ofthe pumps.

Fig. 21 is a diagram of the electrical circuit utilized in the machinewhen the pressing and jiggering mechanism is operated by the modifiedhydraulic system shown in Fig. 20.

Referring more particularly to the drawings and especially to Figs. 1,3, 4, 5, and 6, the machine comprising the present invention includestwo substantially duplicative sections 20, 20 each having a circularbase 21, 21, one side of which is provided with a fiat surface, the flatsurfaces of the sections disposed in engagement with one another andsecured by bolts or other fastening means. The base members 20, 20receive and support upper housing sections 23, 23 which are slightlymore than semi-circular when viewed in plan, the flat sides of thesesections also being disposed adjacent one another. These flat sides arespaced to provide a recess for the reception of the lower portion of aconveyor, designated generally by the numeral 24. As the machinesections are duplicated, only one has been shown in detail and only thisone will be described. Each machine section 20 includes a pair oftelescopic shafts 25 and 26, the latter being tubular to receive theformerv Shaft 25 is journaled at its upper and lower ends as at 27 and28, respectively, while shaft 26 is also journaled in the top wall ofthe upper section and bearings carried by the top wall of the lowersection. The mounting for these shafts thus permits their rotationrelative to the base and one another. In the operation of the machine,shaft 26 is continuously rotated through the provision of a worm andworm wheel, 30 and 31. The worms 30 are carried by a shaft 32 whichextends diagonally across the base section and is journaled in bearing33 therein. One end of the shaft 32 extends to the exterior of the baseand is provided with a pulley for the reception of belts by which motionis transmitted to the shaft. When shaft 32 revolves, the worms 30transmit such rotary movement to the worm wheels 31 which in turntransmit this movement to the shafts 26. Each shaft 26 is providedadjacent its lower end with a gear 35 disposed in meshing engagementwith a similar gear 36 secured to an idler shaft 37. This idler shaft,also, is provided with the driver section 38 of a Geneva transmissionemployed to impart intermittent movement to the shaft 25, the star wheel40 of the Geneva transmission being secured to the lower end of theshaft 25. These Geneva transmissions, shown in Fig. 5, operate in theusual man ner and each is provided with a star wheel having six slots toreceive the pin of the driver. The shaft 25 of each machine section is,therefore, caused to rotate step by step through one revolution whilethe shaft 26 makes six complete revolutions. By intermittently rotatingthe shaft 25, a horizontal carrier secured to the upper end thereof isindexed to successively present each of six mold receiving recessesthereon to each of a plurality of stations. During each period of restof the carriers 41, tWo of the mold receiving recesses are disposed overthe open space between the machine sections. At this time the conveyor24 operates to deposit an ernpty mold in one of the mold receivingrecesses and remove a charged mold from the other recess.

As illustrated in Fig. 2, the conveyor comprises an endless chain 42, tospaced links of which are secured outwardly projecting pins 43. Bars 44are pivotally supported by the pins 43, these bars carrying outwardlyprojecting fingers 45 at their lower ends. The outer extremities of thefingers 45 are formed with rings 46 to receive the molds 47 on which theclay articles are formed. The chain 42 is trained around a sprocket 48,keyed or otherwise secured to a shaft 49. This shaft is journaled inbearings 51 carried by the inner side walls of the base sections 23. Oneend of the shaft 49 has a bevel gear 52 secured thereto, this gearmeshing with a bevel pinion 53 which rotates in unison with the shaft26. Since this shaft rotates continuously, similar con-' tinuousrotation will be imparted by the gears 53 and 52 to the shaft 49 andsprocket 48. The chain 42 will, therefore, move continuously in timedrelation to the operation of the machine sections. After an empty moldhas been deposited on the carrier 41, this member moves to a stationwith which a clay feed pipe 54 registers. As indicated in Figs. 1 and 6,two of these feed pipes are provided for each machine in order that themachine can be continuously operated, the clay being fed through onetube while the other one is being recharged and vice versa.

The clay feeding mechanism is arranged on a floor or balcony above theware-forming machine proper and comprises a pair of substantiallyduplicate units. Each unit includes a hydraulic power cylinder 55, 55A,a clay magazine 56, 56A, and connecting tubular sections 57, 57A, and58, 58A, the latter being elbow shaped in form. power units 55, 55A, andmagazines 56, 56A, are supported on rollers 60 and 61 to permitlongitudinal movement thereof toward and away from the tube sections 57,57A. The clay magazines are secured to the power units and connectortube sections 57, 57A, by clamps 62 of the type shown in Figs. 10 and11. These clamps include pivoted sections 63 and 64 and a Ushaped bail65 which is pivotally secured to the clamp section 63. When the clamp isoperatively positioned, the sections 63 and 64 are swung toward oneanother, the bail 65 is swung over the end of section 64 and a set screw66 is tightened against an abutment on the section 64. The ends of thesections 63 and 64 are thus drawn toward one another which causesinclined surfaces 67 on the inner sides of the clamp sections to slideon similar surfaces 68 formed on collars 70 surrounding the mating endsof the power units, magazines and connecting tubes and force theadjoining ends of these members into leakproof engagement.

After the magazine of one feed unit has been emptied of clay, the powercylinder of the other feed unit is started to force clay from themagazine previously connected therewith. Due to the particular hydraulicsystem employed, the changeover from one clay feed unit to the other isautomatic, the plunger of the exhausted magazine being withdrawn topermit the removal of the empty As illustrated in Figs. 7, 8, and 10,both fluid power cylinders 55, 55A of each unit, a battery of fourwayvalves 71, 72, and 73, a pressure building valve 74, motor driven pumps75 and 76, pressure operated tripping valves 77 and 78, relief valves 80and 81 and tubing to properly connect these elements. Pump 75 drawsfluid, preferably oil from a reservoir 82 through line 83 and deliversthe same via line 84 to the pressure building valve 74. From this valve,the fluid flows through line 85 to the inlet of four-way valve 72. Whenthe spool 86 of this valve is in the position shown in Fig. 13, thefluid under pressure is directed through line 87 to the rear end ofpower cylinder 55. This fluid forces piston 88 in the cylinder 55forward which motion is transmitted by rod 90 to plunger 91 whichengages and propels the clay from the magazine 56. During the forwardmovement of piston 88, fluid is discharged from the forward end of thepower cylinder 55 through line 92 to one of the cylinder ports offour-way valve 71. At this time spool 93 of valve 71 is positioned toconnect line 92 with another line 94 extending to the reservoir 82.

The flow of fluid under pressure through line 87 to power cylinder 55causes the clay in magazine 56 to be expelled through tubes 57, 58 and54 to the forming machine, suitable cut-oif mechanism 89 being providedto sever the clay extruding from tube 54 into bats of the necessarythickness. When the magazine 56 has been substantially emptied, piston88 engages the end wall of the cylinder and pressure builds up in line87 until it is sufiicient to trip valve 77 which is connected with suchline by line 95, and flow through line 96 to the right-hand end offour-way valve 73. This pressure shifts the spool 97 of valve 73 to theleft where it will connect a line 98 leading from pump 76 to a line 100which extends to the left end of valve 71. Fluid flowing from the pump76 through the line 100 to valve 71 causes the spool 93 to move towardthe right where it will connect a line 101 leading from pump 76 to line92 which extends to the forward end of the cylinder 55. Fluid flowing bythis path to cylinder 55 causes the piston 88 to move rearwardly anddraw plunger 91 out of magazine 56 so that it may be removed and a fullmagazine inserted in its place.

Some of the fluid flowing through line 100 is directed through a branch102 to the right-hand end of valve 72 to cause spool 86 to move to theleft where fluid supplied by pump 75 will be directed through line 103to rear end of power cylinder 55A, the fluid serving to move piston 104forwardly and cause similar movement of plunger 105 connected therewith.This plunger operates to expel plastic clay from magazine 56A in thesame manner that piston 88 expelled clay from magazine 56. Duringforward movement of piston 104, fluid is discharged from the frontportion of cylinder 55A through line 106 to the second cylinder port ofvalve 71 which fluid is directed by this valve to the reservoir.

When approximately all the clay in magazine 56A has been discharged,piston 104 will engage the forward end wall of cylinder 55A causingfluid pressure to increase in line 103. This increased pressure will betransmitted by branch 107 to trip valve 78 and will operate this valveto cause fluid under pressure to flow to the left end of valve 73. Thisfluid will shift spool 97 to the right end of the valve 73 wherein fluidfrom pump 76 will be directed through line 108 to the right and leftends of valves 71 and 72, respectively. The admission of fluid pressureto these valves in this manner again directs fluid from pump 75 tocylinder 55 to cause it to resume operation and connects the rear end ofcylinder 55 to tank. It also connects line 106 with pump 76 and line 103with the reservoir thus causing reverse movement of piston 104 andplunger 105 so that empty magazine 56A may be removed and a fullmagazine substituted therefor.

As shown in Fig. 12 the plungers 91 and 105 are provided with valves toeliminate suction on their return strokes. Such strokes are performedmore rapidly than the forward strokes in order that a full magazine maybe substituted for an empty one before the other magazine is emptied.

The pressure building valve 74 is connected in the system between pump75 and valve 72 and is operative to maintain the volumetric delivery ofpump 75 constant at all times whereby the rate of extrusion from tubes54 and 54A will remain constant. As indicated in Fig. 14, valve 74includes a casing 110 having a bore 111 for the reception of a spool 112which controls communication between lines 84 and 85 leading to and frombore 111. Spool 112 has a piston extension 112A which slides in a socket113 constituting a continuation of the bore 111, the socket beingconnected by passage 114 with the inlet pipe 84. Spool 112 is providedwith a socket 115 which registers with a similar socket 116 formed in acap 117 employed to close the open end of the casing 110, the sockets115 and 116 receiving a coil spring 118 which tends to urge spool 112 toa position to prevent communication between lines 84 and 85. The forceof the spring 118 must be overcome by the fluid applied to the end ofextension 112A before communication can be established, therefore, thespring serves to build up the pressure and cause it to be maintained. Athumbscrew 120 is provided to adjust the spring 118 and thus vary thepressure secured by the valve 74.

Fluid lines 121 and 122 branch from lines 100 and 108 and are connectedwith opposite ends of a small power cylinder 123 used to adjust andsynchronize the operation of the cutofl mechanism 89 for the clay, withthe operation of the forming machines so that the bats severed from thefeed tubes will be properly positioned on the molds.

The cut-off mechanism 89, indicated generally in Fig. 1, may be of anysuitable type which will operate to sever the bats from the descendingclay column and deposit the same on the molds. The clay feed tubes 54and 54A are disposed in vertical registration with the first twostations of the table 41 following the loading station where the emptymolds are deposited by the conveyor 24. As the feeding units arealternately operated, the molds may receive the clay bats at eitherstation after which they will be advanced to the third station disposedbeneath and in vertical registration with a pressing head 124.

The head 124 has a die 125 with which the clay bats on the molds areforcibly engaged to be given the general shape of the finished article.Die 125 is held stationary during the pressing operation, the moldsbeing elevated from the carrier table 41 and moved into contact with thedie by a power cylinder designated generally by the numeral 126. Thispower cylinder is shown more indetail in Fig. 17.

In the present embodiment of the invention, the power cylinder 126includes a body 127 of generally cylindrical form disposed with thelongitudinal axis thereof extending vertically. A flange 128 is providedat the lower end of the body for engagement with a flange 129surrounding an opening 130 formed in the top wall of the base 21.Suitable securing means 131 are employed to maintain the position of thebody. A chamber 132 extends longitudinally of body 127 to slidablyreceive a piston 133, the end portions of the chamber stationarilyreceiving sleeve-like members 134 which serve as guides for piston rods135 projecting from the upper and lower ends of the piston 133. End caps136 close the ends of the chamber 132 and hold the guides 134 inposition, the caps being provided with packing rings 137 to strip fluidfrom the rods during movement of the same out of the chamber.

As illustrated in Fig. 3, the upper end of the upper piston rod 135 isconnected with the lower end of a push rod 138 disposed for verticalsliding movement in a bearing 140 carried by the horizontal top wall ofthe base section 23. At its upper end, the rod 138 is connected with anadaptor 141 to which is secured a recessed plate 142. This plate islined with resilient material 143 so th t when the plate is en g d witha m the la er will be protected from injury. As shown in Fig. 1, thetable-like carriers 41-are provided with a plurality of circularlyshaped recesses which open to the outer edge of the table. Theserecesses 145 are disposed at the stations of the table between theperiods of movement of the latter. When the tables are at rest, thepower cylinder 126 operates to move the adaptor 141 and its plate 142upwardly through the recess 145 located in registration therewithcarrying with it the mold which was disposed in the recess. Continuedoperation of the power cylinder serves to move the mold upwardly untilthe clay bat thereon is forced into engagement with the die 125. Thepower cylinder 126 is then operated to lower the mold to its recess 145on the carrier 41 for advancement to the next station. Of course, thepower cylinder continues to operate after the mold has been positionedon the carrier until the recessed plate 142 is disposed out of the pathof movement of the carrier 41. As considerable force is imparted to themold in the pressing operation by the power cylinder 126, this member isbraced at its lower end by a cup-shaped device 146 supported on theupper end of a threaded post projecting upwardly from the base member,the post being designated by the numeral 147.

It is desirable in the operation of the machine to avoid jerkiness orsudden starting and stopping in the movement of the mold to the pressingposition. A control mechanism, designated generally by the numeral 150,has

been provided to control the operation of the power cyli inder 126. Thiscontrol mechanism is illustrated in detail in Figs. 16 and 17. Itcomprises a body 151 supported on the power cylinder by a bracket 152.The body 151 has a longitudinally extending bore 152 extendingtherethrough which bore intersects a plurality of longitudinally spacedchambers 155 to 159 inclusive. Chamber 155 is located adjacent thecentral portion of the bore 153 and is connected with a source of fluidunder pressure by line 161. Chambers 156 and 157 are disposed onopposite sides of the chamber 155, the former being connected by line162 with the lower end of the chamber 132 while the latter is connectedby tube 163 with the upper end of said chamber. The chambers 158 and 159arelocated on the outer sides of the chambers 156 and 157, these outerchambers being connected by a passage 164 which is in turn connected bya tube 165 with the exhaust. The bore 153 slidably receives a sleeve 166which is provided at spaced intervals with radial ports registering withthe chambers 155 to 159.

Sleeve 166 slidably receives a spool 168 which is formed with spacedgrooves 170 and 171 employed to connect certain of the chambers 155 to159. Sleeve valve 166 is closed at one end by a wall 172 in which isformed a socket 173 for the reception of a coil spring 174, this springengaging the inner end of the spool 168. The tendency for the spring 174to expand tends to cause relative movement between the sleeve and thespool which movement is precluded except at desired times by cam members175 and 176 engaging rollers 177 and 178 journaled in the outer ends ofthe sleeve 166 and spool 168, respectively. Normally, the sleeve and thespool are so positioned relative to one another that a land 180 betweenthe grooves 170 and 171 precludes communication between the chamber 155and the interior of the sleeve 166. The unreduced portions of thespool'168 at the outer ends of the grooves 170 and 171 also block portsin the sleeve extending to the chambers 158 and 159. When the parts arethus positioned, no fluid flow to or from the chamber 132 can takeplace. The piston 133, therefore, will be maintained in its presentposition.

The front end of the body 151 is closed by a cap 182 which carries apacking ring 183 of resilient material employed to strip hydraulic fluidfrom the sleeve 166 during its movement out of the body 151. Theopposite end of the body is closed by a fitting 184 having an opening185 through which the outer portion of the spool 168 projects. Thisopening communicates at its outer end with a vertically extendingopening 186 through which a rod 187 is adapted to move. This rod carriesthe cam 176 and is connected at its upper end by an arm 188 with thepiston rod 135. Thus, when the piston 133 moves in the power cylinder,similar motion will be imparted to the rod 187 through the arm 188. Theupper and lower ends of the opening 186 communicate with the interior ofcap shaped members 190 and 191 respectively. Member 190 has an openingat its upper end through which the rod 187 projects, this opening beingprovided with resilient packing 192 used to strip hydraulic fluid fromthe rod 187 as it moves out of the member 190. Normally, the lowermember 191 is filled with hydraulic fluid to maintain the rod 187lubricated for sliding movement in the fitting 184. As will be apparentfrom Fig. 17, the cam member 176 is of wedged shaped form and in thisinstance the wedge is so arranged that the widest portion thereof is atthe lower end of the rod 187; thus, when the piston 133 moves in anupward direction the cam 176 will cause the spool 168 to move inward inthe body 151. It will be apparent, of course, that the piston 133 cannotmove until fluid under pressure is supplied to the lower end of thechamber 132. To provide for the admission of pressure to the lower endof chamber 132 sufficient relative movement between sleeve 166 and spool168 must take place to connect port 156 with the inlet port 155 and port157 with the outlet port 158. This relative movement is secured throughthe movement of sleeve 166 by spring 174 and cam 175 as the latterrevolves in unison with shaft 26. When cam 175 moves from the positionshown in Fig. 16, spring 174 will cause sleeve 166 to move toward theright while spool 168 is held in the position shown. This relativemovement establishes communication between the ports in the sleeveregistering with groove 155, and the groove 171 and fluid under pressuremay then flow from line 161 and groove 155 to groove 156 and line 162leading to the lower end of chamber 132. The force of this fluid tendsto urge the piston 133 in an upward direction and to discharge fluidfrom the upper end of chamber through line 163 and grooves 157, 170,ports registering with groove 158 and outwardly through line 165 to thefluid reservoir.

From Fig. 17, it will be observed that as piston 133 moves in an upwarddirection, cam 176 will also move upwardly and the inclined surfacethereof will cause spool 168 to be moved toward the right which movementwill tend to interrupt the flow of fluid to and from the lower and upperends of chamber 132. The speed of movement of the piston 133 and themechanism operated thereby may thus be automatically controlled, theshapes of the cams determining the degree of opening of the valve and,consequently, the speed of movement of the piston. It will be apparent,from Fig. 16 and the foregoing description, that, since spool 168 hasmovement imparted thereto by movement of the piston 133, it is necessarythat the sleeve 166 be moved before motion can be imparted to the piston133 through the admission of fluid to the lower end of chamber 132. Itwill also be apparent that sleeve 166 must move outwardly of body 151 ortoward the right as viewed in Fig. 16. To secure this motion, cam 175must be so formed that, during initial rotation of the shaft 26, thesurface of the cam will move away from the body 151 allowing spring 174to expand and force sleeve 166 toward the right to maintain the roller177 in contact with the surface of the cam. As soon as fluid underpressure flows into the lower end of chamber 132, the piston 133 willstart its upward movement imparting similar movement through arm 183 torod 187 and cam 176 which will cause spool 168 to follow sleeve 166. Thecam 175 is so formed that a uniformly accelerated and decelerated motionwill be imparted to piston 133. After the bat has engaged the die,pressing force will be continued for the required time, the shape of thecam 175 being such as to maintain communication between the inlet port155 and the lower end of the chamber 132. After the necessary time haselapsed, the rotation of shaft 25 will cause cam 175 to force sleeve 166into body 151 to interrupt communication between grooves 155 and 156 andbetween grooves 157 and 158. Piston 133 and the mechanism carriedthereby is lowered by supplying the upper end of chamber 132 with fluidunder pressure and connecting the lower end of this chamber with thereservoir. These operations are secured through the continued movementof the sleeve 166 toward the left, as viewed in Figs. 16 and 17, untilthe ports in registration with inlet groove 155 are opened to groove 170in spool 168 and ports registering with outlet groove 159 are opened togroove 171 in this spool. When these ports are so positioned, fluidunder pressure is supplied to the upper end of chamber 132 and piston133 will start to move in a downward direction. This movement of thepiston imparts similar movement to cam 176 which in turn permits spring174 to move spool 168 to the left to regulate the degree ofcommunication between grooves 155 and 170 and between grooves 159 and171, The speed of descent of piston 133 is thus controlled in the samemanner as the speed of elevation. The admission of fluid under pressureto the upper end of the chamber to cause the piston 133 to descend movesthe mold with the bat thereon away from the die and deposits the same onthe table 41 for advancement to the next station.

At this station the clay bats are moved into engagement with a jiggeringhead indicated generally by the numeral 200. This head is also spacedabove the table 41 and the molds with the bats thereon are movedupwardly to a position wherein the bats may be operated upon by one ormore rotatable scraper blades 201, a power cylinder of the type shown at126 also being used to move the molds and bats toward and away from thejiggering head. The mechanism for performing the jiggering operation maybe of any type, one such mechanism being illustrated in detail in Fig.15. The mechanism shown in Fig. includes a sleeve 202 which projectsdownwardly through a hole 203 formed in a shelf 204 supported over therotatable table 41 by columns 205. A second sleeve 206 is keyed forlongitudinal sliding movement in the sleeve 202 and-one end is threadedas at 207 for cooperation with a similarly threaded adjusting ring 208.The ends of the sleeve 206 receive anti-friction bearings 210 whichserve to rotatably support a hollow shaft 211 to the lower end of whichthe blades 201 are secured. The housing 212 is disposed around the upperend of the sleeve 202 and ring 208 and this housing is surmounted by asecond housing section 213 which also supports an anti-friction bearing214 at its upper end, this anti-friction bearing also serving as ajournal for the hollow shaft 211. The upper end of the shaft 211 has aset of pulleys 215 secured thereto to receive a V-belt 216 employed totransmit rotary motion from a motor 217 mounted on the shelf 204 to theshaft 211. When the motor 217 is operated, rotary motion will beimparted by the belt and the pulleys to the shaft 211 which will revolveand impart through the scrapers 201 secured thereto a scraping action onthe clay bat supported in contact with the members 201.

When the bats are scraped in this manner, waste material is separatedtherefrom and this material must be removed from the bat. To effect thisoperation, air or water, or both, may be directed against the ware injet form by means of nozzles 218 and 220 also supported on the lower endof the shaft 211. Fluid is conducted to these nozzles through theinterior of the shaft and a tube supported therein. A swivel 221surrounds the upper end of the shaft 211 and serves to admit air andwater to the interior of the shaft and the tube from a pair of tubes 222and 223 extending from suitable sources of supply. As the scrapers 201revolve, the waste will be thrown by centrifugal force into a trough 224surrounding the lower portion of the jiggering head. The trough alsosurrounds the mold 47 and the bat when the same is elevated for thejiggering operation. A scraper 225 is suspended from a ring-like member226 which is secured to a ring gear 227 supported for rotation aroundthe lower end of the opening 203 in the shelf 204. This motion isimparted to the ring gear by a pinion 228 secured to the lower end of avertical shaft 229 projecting from a gear case 230 carried by anelectric motor 232, this motor being mounted on the upper surface of theshelf 204. When the motor 232 is operated, rotary motion will beimparted by the shaft 229 to the pinion 228 which in turn will cause thering gear 227 to revolve carrying with it the member 226 from which thescraper 225 depends. As this member moves along the trough 224, it willscrape the waste from the bottom and sides thereof and cause it to bedischarged through a chute 233 to a suitable receptacle not shown. Thehousing 212 has a worm 234 journaled therein for cooperation with teethprovided on the member 208 to effect the vertical adjustment of thesleeve 206. Rotary movement is imparted to the worm 234 by an exteriorlydisposed hand wheel 235, This means serves to effect the raising andlowering of the scrapers 201 whereby the thickness of the final ware maybe determined. When the scraping operation has been completed, the mold47 with the bat thereon will be lowered into position on the carrier 41which will then move the mold to the next station for removal by theconveyor 24. The cycle of a mold through a ware-forming machine is thuscompleted.

As shown in Fig. 1 and as previously mentioned, the machine 20 iscomposed of two duplicative sections. Each section has a station wherethe conveyor deposits the empty molds, two stations where clay isalternately applied to the molds, pressing station, a jiggering stationand a station where the formed articles are removed with the molds bythe conveyor. The molds are removed from the table for forming andjiggering operations only at the pressing and jiggering stations. Eachof these stations is provided with a power cylinder 126 for elevatingthe mold into the forming position. The power cylinders 126 areautomatically operated and are connected in a hydraulic system showndiagrammatically in Fig. 18. This system may be of many different typesbut the one selected for illustration supplies a relatively highpressure to the power cylinders used in the pressing operation and alower pressure to the cylinders at the jiggering stations. The systemshown in Fig. 18 includes reservoir 250, which is in the form of a tank,which also serves as a base for an electric motor 251. Each end of thearmature shaft is connected with a hydraulic pump 252 and 253. Thesepumps may be of any suitable type but one thereof must be capable ofgenerating high pressure. The hydraulic system shown in Fig. 18 issubstantially two hydraulic systems arranged in parallel, the pumpsthereof being operated by a single motor. Pump 252 is arranged in ahydraulic circuit including the power cylinders 126 for operating thepressing devices. The other hydraulic circuit, including pump 253,supplies fluid under pressure to the power cylinders 126 used inelevating the clay bats to the jiggering mechanism. Both of thesesystems include an inlet line 254 extending from the reservoir to inletof the pumps, the lines 254 containing strainers 255. Outlet lines 256extend from the pumps to relief valves 257, check valves 258 beingarranged in lines 256 to prevent reverse flow of the fluid. From therelief valves 257, fluid flows through lines 260 to solenoid operatedby-pass valves 261 from which lines 262 and 263 extend to the reservoirand an accumulator 264 respectively. Outlet lines 265 extend from thereservoirs 264 to the control valves of the power units. The lines 265contain check valves 267 to prevent the flow of fluid back to theaccumulators. In Fig. 18 only the power 11 cylinders for one section ofthe machine have been illustrated but it will be obvious that eachsection of the hydraulic system will have two or more of such powercylinders depending upon the number of machines serviced by thehydraulic system or the number of pressing and jiggering stations oneach machine.

The accumulators 264 have pistons 268 disposed for movement therein inresponse to the accumulation of hydraulic fluid. The spaces in theaccumulators above the pistons 268 receive air or other fluid employedto preload and apply pressure to the pistons to force the hydraulicfluid from the accumulators. The high pressure section of the hydraulicsystem has a cylinder 270 of cornpressed gas connected with the upperend of the accumulator to initially charge the same withcounter-balancing pressure. The upper end of the container 270 isequipped with a regulator 271 from which a line 272 extends to the upperend of the accumulator 26 5. Valves 273 and 274 are disposed in the line272 and an outlet branch 275 thereof to control the entrance of the airor other compressed gas into and out of the upper end of theaccumulator. The low pressure section of the hydraulic system may alsobe supplied with a container of compressed air or other gas forpreloading the upper end of the accumulator in this section of thesystem or, if desired, such accumulator may be connected with a suitablesource of compressed air. In any event, a regulator 271 is necessary tomaintain the proper pressure in the upper end of the accumulator. Bothsections of the hydraulic system are automatic in operation, that is,the power cylinders will only be operated when the proper ratio offluids under pressure obtains on the opposite sides of the pistons ordiaphragms 268 in the accumulators 264. To eifect this control, anelectrical circuit, such as that illustrated diagrammatically in Fig.19, is employed. This electrical circuit includes a number of switchesand solenoids which are actuated by elements in the hydraulic system,or, conversely, they actuate elements in the hydraulic systemthemselves. Certain of the switches or solenoids are employed to securethe proper sequence of operations of the various parts of the machine.These will appear as the description proceeds.

As illustrated in Fig. 18, the piston or movable diaphragm of eachaccumulator has a rod 273 projecting therefrom which rods are providedadjacent the outer end with a cam shaped enlargement 280. Theseenlargements serve to actuate switches 281 to 283 inclusive. Theswitches bearing the odd numbers are actuated by the movement of thepiston in the high pressure accumulator, while those bearing evennumbers are actuated by the piston in the other accumulator. Switches231 to 238 inclusive are termed limit switches. Other limit switches 291to 294 are also provided, these being disposed in positions to beactuated by the arms 188 of the power units when these elements move totheir lowermost positions. The limit switches 292 and 294 which areactuated by the power cylinders on the second section of the machine areshown only in the diagram in Fig. 19. Another limit switch 295 isdisposed adjacent one of the control valve actuating cams 175. Duringthe operation of the machine, this limit switch serves to coordinate theoperation of the various parts of the ware-forming machine, after thesame has been shut down. As shown in Figs. 17 and 18, each control valve150 is provided with a solenoid operated lock 296, the solenoids beingnumbered 297 to 300, inclusive. The solenoids 298 and 300 used in theoperation of the second section of the machine are shown onlydiagrammatically in Fig. 19. The solenoids for the by-pass valves 261 inthe hydraulic system are designated by the numerals 301 and 302.

In addition to the limit switches and solenoids previously mentioned,the electrical circuit, as shown in Fig. 19, includes a plurality ofrelay and solenoid operated switches for interlocking the operation ofthe table and conveyor operating motor, the motors for the hydraulicsystem of the clay feed and the motor for the hydraulic system of thepressing and jiggering mechanism. When no current is flowing through theelectrical system, certain of the switches or contacts will be normallyopened while others will be normally closed. Fig. 19 illustrates thecircuit with the switches or contactors in their normal positions whenno current is flowing in the circuit. Fig. 19 only those portions of theelectrical circuit for the machine motor and the clay feed motor havebeen illustrated which are necessary to clearly indicate the interlockbetween the various machines or parts thereof. in the electricalcircuit, the characters L1, L2, and L3 designate the power lines. Leads303, 304 and 305 extend from these lines to contacts of a relay switchdesignated generally by the numeral 306. The other contacts of thisswitch are connected by leads with the motor 251. The lines L1 and L3are also connected with the primary side of a transformer 307 whichsteps the voltage down for use in the major portion of the electricalcircuit. The operation of switch 306 is controlled by a relay switch 308which includes spaced contacts 309, a contactor bar 310, start and stopswitches 311 and 312, and a coil 313. This control circuit is connectedwith the secondary of the transformer 307 in the manner shown in Fig. 19so that, when the switch 311 is closed, the circuit will be completed tothe coil 313 which, when energized in this manner, closes switch 308which also completes the circuit for the coil 313. The start button 311may then be released. When coil 313 is energized, switch 306 is alsoclosed to supply current to the motor 251.

The electrical control circuit also includes two relay circuits havingfive sets of contacts each. These sets of contacts are designated by thenumerals 315 to 324 inclusive. The odd numerals are arranged in onerelay circuit and the even numerals designate contacts in the otherrelay circuit.v The coils of these relays are designated by the numerals325 and 326. The coils 325 and 326 are arranged in parallel brancheswhich are supplied with current from the secondary of the transformer307 through a line 327 in which a relay switch 328 is disposed. Thebranch circuit is completed by a line 329 extending from the coils 325and 326 to the secondary of transformer 307. The line 329 also containsthe switch 308. The flow of current to the coils 325 and 326 can only besecured by closing switch 328 through the energization of a coil 330which is disposed in the electrical circuit for the motor 331 employedto operate the ware-forming machine and the conveyor. This circuitincludes motor start and stop switches 332 and 333, respectively, thecoil 330 and an electro-rnagnetic switch 334 which includes a coil 335.The motor 331 is started in operation by closing the switch 332 toinitiate current flow through coil 335.

This current flow attracts the core of the switch 334 and closes thecontacts thereof. The switch 332 may then be released. Since switch 334is closed, current will continue to flow through coil 335 which will inturn maintain switch 334 closed. Current will also flow through coil 330and effect the closure of switch 328. Current is still prevented fromflowing from the secondary of transformer 307 through the coils 32 5 and326 because the branches of the circuit, including these coils, containswitches 337 and 338 which are normally open, that is, when current isnot flowing through the circuit. Switches 337 and 338 are controlled inoperation by coils 341 and 342, respectively, which are arranged incircuit branches 3 an 3 4 cont ining sp c d s f con ts 21 n 322controlled in turn by Coils 3 25 and 326. The circuits 343 and 344 alsoinclude the limit switches 285 and 286, respectively. Coils 341 and 342also control normally closed switches 345 and 346. These switches arearranged in branch circuits 347 and 348 containing switches 351 and 352and coils 353 and 354. In addition to governing the operation of theswitches 351 and 352, the coils 353 and 354 serve to operate normallyclosed 13 switches 355 and 356 which are arranged in parallel branchcircuits 357 and 358 including the spaced pairs of contacts 319 and 320,respectively, the contacts of each pair being normally connected whenthe coils 325 and 326 are de-energized. Branch circuits 357 and 358 aredirectly connected with the current supply lines L1 and L3 when themanual switch in line 303 is closed. Circuit 357 includes limit switches291 and 293 and a field coil of solenoid 301 of one valve 261 whilebranch 358 includes limit switches 292 and 294 and field coil 302 of theother by-pass valve 261. A synchronizing branch circuit, designated bythe numeral 360, includes a magnetically operated switch 361, spacedsets of contacts 318 and 317 and a field coil 362 which controls theoperation of the switch 361 and a second switch 363 disposed in a branchcircuit including switches 315 and 316 as well as solenoids 297 to 300inclusive. Switches 315 and 316 are controlled by coils 325 and 326.These coils also control the operation of switches 323 and 324 which arearranged in a circuit 364 controlling the operation of the motors 365used to operate the pumps 75 and 76 in the clay feed hydraulic circuit.The circuit 364 also includes start and stop switches 366 and 367, themagnetic switch 368 and the coil 370. The coil 370 will not hold theswitch 368 closed until the switches 323 and 324 are also closed. Theclay feed mechanism is thus interlocked with the pressing and jiggeringmechanism, the former depending upon the operation of the latter for itsoperation.

Power cylinders 126 are inoperative when the machine is shut down andthe pistons 133 will be in their lowermost positions as will also thecam rod 187 and earns 176. At this time, the spool 168 of each controlmechanism 150 will be fully retracted and the sleeve valve 166 of eachcontrol unit will be at its innermost position where it will be held bythe solenoid operated lock 296, this lock being spring-pressed tooperative position when the solenoid is deenergized. Since the locks 296hold the sleeves 166 in their innermost position, no fluid will besupplied to the power cylinders 126 until the solenoids 297 to 300inclusive, are energized.

The operation of the pressing and jiggering hydraulic circuit may bebest understood by referring to Figs. 18 and 19. When the machine is tobe operated, the regulators 271 are set for the desired pressures,valves 274 are closed and valves 273 opened to admit preloading gas tothe accumulators 264 above the pistons 268. The motor start switch 332is then actuated to initiate the operation of the machine and theconveyor. The closing of switch 332 energizes coil 330 which closesswitch 328. This operation will have no effect, however, until eitherswitch 337 or 338 is closed which cannot be done until the correctvolume of fluid at the proper pressure is contained within theaccumulator 264 in the corresponding section of the hydraulic system. Tosecure this condition, the switch 311 is closed to effect theenergization of coil 313 which in turn closes switch 308 as well asswitch 306 which controls current flow to the motor 251. As previouslymentioned, when the machine is idle, the pistons of the hydraulic units126 will be at their lowermost positions in which the arms 188 will beengaged with the switches 291 to 294, inclusive, to hold the same inclosed positions. Also when the machine is idle, the enlargements 280 onthe rods 278 extending from the accumulators will be disposed at thelower end of their travel at which positions they will hold switches 281and 282 in closed positions. Thus when switch 308 is closed, currentwill flow through the line 327 through switches 281 and 282, coils 353and 354, and switch 308 to energize the coils 353 and 354 and closeswitches 351 and 352. Current will then flow through switches 345 and346 and circuits 347 and 348 through switches 351 and 352 and coils 353and 354 to hold switches 351 and 352 closed. When coils 353 and 354 areenergized, switches 355 and 356 will be held in open positions toprevent the flow of current to the solenoid field coils 301 and 302.When these coils are de-energized, that is, coils 301 and 302, by-passvalves 261 will be in condition to direct fluid from the pumps 252 and253 into the lower ends of the accumulators 264. When motor 251 isoperated, the hydraulic fluid will be supplied to the accumulatorscausing the pistons 268 therein to move upwardly in opposition to theair or other compressible gas with which the upper ends of theaccumulators have been preloaded.

The cam enlargements 280 will move away from switches 281 and 282permitting them to open. But, since switches 351 and 352, 345 and 346are closed, the branch circuits 348 and 347 will be unaffected. Whensuflicient fluid has been pumped into the accumulators 264 to raise thecams 280 to the position wherein switches 285 and 286 are actuated, thefluid supply will then be in the operating range. When switches 285 and286 are closed, current will be supplied to the coils 341. and 342 toenergize same. When these coils are energized, switches 345 and 346controlled thereby will be moved to an open position thus discontinuingcurrent flow through circuit branches 347 and 348. Coils 353 and 354will be de-energized permitting switches 351 and 352 to open andswitches 355 and 356 to close. Branch circuits 357 and 358 would then becompleted except for the fact that, when coils 341 and 342 areenergized, switches 337 and 338 operated thereby will be closedcompleting the circuits including coils 325 and 326. When these circuitsare closed, all the switches controlled by coils 325 and 326 will beactuated. Among these switches are two normally closed switches 319 and320 arranged in branch circuits 357 and 358.

When the coils 325 and 326 are energized, switches 319 and 320 will beopened to prevent the flow of current through branch circuits 357 and358. When coils 325 and 326 are energized, another pair of switches 321and 322 are closed which complete circuits, including the coils 341 and342, thus maintaining the supply of current to the coils even thoughswitches 285 and 286 may be opened. Switches 323 and 324 disposed incircuit 364 of the clay feed mechanism are also closed when coils 325and 326 are energized. At this time, the clay feed mechanism may bestarted in operation by pressing the start switch 366 which initiallyenergizes the coil. 370 to effect the closing of the switch 368. Currentmay then flow through the circuit 364 and, as long as switches 323 and324 are closed, coil 370 will be energized to maintain switch 368 in aclosed position. The mechanism is now in position to start theware-forming operations. The pressing and jiggering operations cannot beperformed, however, until cam 175, which is provided with a switchactuating projection 375, moves to a position to actuate the limitswitch 295. When this switch is closed, coil 362 will be energized thusclosing switch 361. When switch 361 is closed, current may then flowthrough this switch, switch 318, switch 317, and coil 362 which will becontinuously energized until current flow is discontinued by the openingof any one of the three switches in this circuit.

When coil 362 is energized, it will also close switch 363 and currentmay then flow through the circuit controlled by this switch whichcircuit includes switches 315 and 316 as well as solenoids 297 to 300.When the solenoids are energized, looking pins 296 will be withdrawnfrom the path of movement of the sleeves 166 in control valves and thesevalves may then be operated by the cams 175. When the valves are sooperated, fluid will be supplied to the power cylinders 126 of thepressing and jiggering mechanisms. The cams, of course, are so arrangedon the shafts of the machine sections as to secure the proper sequenceof operation.

In the event the volume of air in either accumulator should beexcessively lowered for any reason, the piston in that accumulator willbe elevated until the cam enlargement 280 actuated thereby engages thetopmost limit switch identified in the high pressure circuit by thenumeral 287 and by the numeral 288 in the lower pressure circuit. Ifeither of these switches is actuated due to a low air volume, thecircuit containing that particular switch will be opened, discontinuingthe flow of current through the coils 325 or 326 disposed in thecircuit. When either of these coils is de-energized, all the switchescontrolled thereby will be actuated. Let us assume, for example, thatswitch 287 is actuated due to a low air volume in the high pressureaccumulator. When switch 287 is open, current flow will be discontinuedthrough coil 325 permitting all the switches 315, 317, 319, 321 and 323controlled thereby to be actuated to their normal positions. Switch 323will be open, thus opening the circuit 364 for the clay feed mechanism.The clay feed will, therefore, be interrupted until the operatingcondition of the hydraulic system for the pressing and jiggeringmechanism is restored. When switch 321 is open, coil 341 will bede-energized and switch 345 will close. Branch circuit 347 will beunafifected, however, since switch 351 is open. When the coil 325 isde-energized, switch 319 will close; switches 315 and 317 will open. Theopening of switch 317 deenergizes coil 362 permitting switches 361 and363 to open and prevent current flow through the circuit includingsolenoids 297 to 300. When these solenoids are de-energized, the controlvalves 150 will be locked in closed position after the cams 175 move thesleeves 166 into their innermost positions. The pistons in the powercylinders 126 will, at this time, be in their lowermost positionswherein switches 291 and 293 will be closed completing the circuit forthe solenoid 301 of the bypass valve 261 in the high pressure system.When this valve is operated by the solenoid, the fluid supplied by pump252 will be dumped to the reservoir 250. The accumulator will then berecharged with air or other compressible gas which will cause the piston268 to descend until the cam 280 closes switch 281. This switch controlsthe initial flow of current t coil 353 which actuates switches 351 and355.

When coil 353 is energized, switch 351 will be closed and current maythen flow through circuit 347 which includes the coil 3S3, switch 351then being maintained closed regardless of the position of switch 281.Switch 355 will be opened when coil 353 is energized and current flowthrough branch circuit 357 will be discontinued. Solenoid 301 will thenbe de-energized, permitting valve 261 to connect pump 252 with the lowerend of the accumulator 264. Fluid pressure will be built up in theaccumulator causing the piston 268 to move upwardly which will in turnmove cam 280 upwardly as in the initial operation. When the cam 280again actuates switch 285, coil 341 will be energized as before to causethe closing of the switch 337 and the energization of the coil 325. Allthe switches controlled by this coil will be operated again aspreviously, switch 323 in the clay feed circuit being closed to placethis circuit in condition for operation of the clay feed mechanism whichmay then be accomplished by closing the starter switch 366. When coil325 is energized, switch 317 will be closed and, when switch 295 isagain closed due to the rotation of the shafts in the machine sections,coil 362 will be energized to close switch 361. The circuit 360 willthen remain energized even though switch 295 is opened. When coil 362 isenergized, switch 363 is closed and current will flow through thesolenoids 297 to 300, inclusive, placing the control valves 150 inoperating condition. Operation of the pressing and jiggering mechanismmay then be resumed.

If the air pressure in the low pressure section of the hydraulic systemshould be lowered excessively, the system will shut down and berecharged in the same manner just described in connection with the highpressure section of the system. In either event, the operation of thevarious pressing and jiggering mechanisms will be maintainedin propersequence, since they are always stopped ing the starter switch 366 aftereither the high or low pressure section of the hydraulic system isrecharged.

From the foregoing, it will be apparent that a wareforming machine hasbeen provided which is fully automatic in operation, has hydraulicallyoperated clay feed mechanism designed to maintain a constant supply ofclay for continuous operation, has hydraulically operated means forpressing the ware and moving the same into jiggering position, theseoperations being performed at the maximum speed without affecting thequality of the finished ware and has the mechanism for performing thevarious operations so interlocked that, in the event of failure orincorrect operation of any one thereof, the operation of the others willbe suspended until the condition causing the incorrect operation isremedied.

The hydraulic system for the power unit of the pressing and jiggeringmechanism may be modified in many ways. For example, Fig. 20 shows ahydraulic system diagrammatically wherein the power units for thepressing and jiggering mechanism are operated by fluid at the samepressure. This system includes a single accumulator to which fluid underpressure may be supplied by either of a pair of motor-driven pumps. Thismodified hydraulic system is governed in operation by a modifiedelectrical circuit illustrated diagrammatically in Fig. 21. This circuitis so arranged that either of the electrical motors for driving thehydraulic pump may be operated, the circuit including switch mechanismfor preventing the simultaneous operation of the motors. The hydraulicsystem shown in Fig. 20 includes a reservoir 380 from which a pair oflines 381 and 382 extend to a pair of fluid pumps 383 and 384 which aredriven by electric motors 385 and 386. Outlet lines 387 and 388 extendfrom the pumps 383 and 384 and are connected as at 390 to a fluid supplyline 391. The lines 387 and 388 contain check valves 392 to preventreverse flow of fluid therethrough when either of the pumps 383 and 384are not in operation.

The supply line 391 is connected with a pressure relief valve 393 ofconventional construction by which the pressure in the supply line 391is prevented from exceeding a predetermined value. The line 391 alsocommunicates with a solenoid operated valve 394 corresponding infunction and operation to the solenoid valves 261 in the hydraulicsystem disclosed in Fig. 18, that is, to dump the fluid from thepressure system to the tank or reservoir preparatory to recharging theaccumulator with oil and gas under pressure. The line 391 extends to theaccumulator 395 which corresponds in function and operation to theaccumulators in the hydraulic system shown in Fig. 18.

The accumulator 395 has a piston 396 disposed for movement therein whichpiston divides the accumulator into oil and gas pressure zones 397 and398 respectively. The latter zone is connected by a line 400 with acompressed gas container 401, the line 400 being provided with apressure regulator 402, a control valve 403, a check valve 404, and ableeder valve 405. The latter valve may be utilized to permit the escapeof gas from the zone 398 in the event too much gas is supplied to theaccumulator. A piston rod 406 projects from a piston 396 and is providedwith a cam enlargement 407 for operating each of a series of switches408 to 411 inclusive. These switches are contained in the electricalcircuit disclosed in Fig. 21 and function to control the operation ofsome of the electrical mechanism forming a part of

